The present invention relates to a method for producing napped surfaces that are lightly and irregularly textured, by coating a panel of backing material with an adhesive, covering it with short textile fibers to form pile on it, preferably in an electrical field, hardening the adhesive, and then mechanically deformating the pile.
Such a method is disclosed in German Pat. No. 1,085,795. It is intended for the production of moire-like patterns and the procedure is such that the napped surface, after the adhesive has hardened, is moistened with waterproofing solutions and then the tiny fibers are bent over at individual locations by pressing them with a pressing member while simultaneously rotating the pressing member, whereupon the surface is dried. The panels of backing material for the nap layer in that patent are planar structures of textile fibers or the like, for example, woven textiles, nonwoven materials or the like. It has been found, however, that other surfaces can also be treated, for example thin plastic sheets, plates of suitable materials and the like. The selection of pile fibers is a significant factor in the success of the process. German Pat. No. 1,085,795 recommends the use of rayon fibers, which are somewhat longer than the textiles previously employed to form the nap but whose length generally is not more than 1.5 mm. In contrast thereto, fibers having a length of about 3 mm or even somewhat more are used to produce moire-type patterns.
The prior art method is suitable merely for the production of relatively coarse structures. If finer structures are to be produced, for example for the manufacture of suede-like surfaces, longer fibers are unsuitable and it is necessary, in departure from prior art recommendations, to use particularly short fibers. These again can no longer be deformed according to the prior art methods so that the fine iridescent effects of suede cannot be produced with these methods.